1. Field of the Invention
The present invention relates to a bowstring drawing assembly for a bow, and more particularly to a bowstring drawing assembly for a bow that can be operated easily and has a simple structure with low costs.
2. Description of Related Art
A conventional bowstring drawing assembly for a bow comprises a mounting frame, at least one winch device and a transmitting device. The at least one winch device is mounted on the mounting frame. The linking device is connected to the at least one winch device. When using the conventional bowstring drawing assembly for adjusting a bowstring of the bow, putting the bow on the mounting frame and rotating the at least one winch device, the transmitting device will move relative to the mounting frame to bend the two limbs of the bow. Then, the bowstring can be adjusted. However, rotating the at least one winch device is laborious and the conventional bowstring drawing assembly further needs a non-return device to prevent the at least one winch device from reversing.
Another conventional bowstring drawing assembly for a bow comprises a mounting frame, a piston cylinder, two struts and two arms. The piston cylinder is mounted on the mounting frame and has a piston rod. The struts are pivotally connected to the piston rod of the piston cylinder. The arms are respectively connected to the struts opposite to the piston rod. When using the conventional bowstring drawing assembly for adjusting the bowstring of the bow, putting the bow on the mounting frame and starting the piston cylinder. Then, the struts will move relative to the mounting frame by the piston rod and the arms that connected to the struts will bend the limbs of the bow. However, the piston rod of the piston cylinder has a fixed stroke and this will limit the bending range of the limbs of the bow.
Furthermore, other conventional bowstring drawing assembly for a bow comprises a mounting frame, an operating device and a transmitting device. The operating device has a threaded rod and operating handle. The threaded rod is movably connected to the mounting frame and has a first bevel gear. The operating handle is rotatably connected to the first bevel gear of the threaded rod by a second bevel gear. The transmitting device is connected to the threaded rod. When adjusting the bowstring of the bow, putting the bow on the mounting frame and rotating the operating handle to make the threaded rod moving relative to the mounting frame by the engagement of the bevel gears. Then, the transmitting device will move relative to the mounting frame to bend the limbs of the bow by the operating device. The operating device of the conventional bowstring drawing assembly also can be a hoisting jack or a gear wheel-rack device.
Although the conventional bowstring drawing assembly can provide a bowstring adjusting effect, but the conventional bowstring drawing assemblies for a bow aforementioned have a complicated structure and this will make the assembling troublesome and will increase the cost of production. Furthermore, mounting and locating the bow on the conventional bowstring drawing assembly is inconvenient.
To overcome the shortcomings, the present invention tends to provide a bowstring drawing assembly for a bow to mitigate or obviate the aforementioned problems.